1. Field of the Invention
The present invention relates to a method of mounting and demounting a semiconductor device, a device for mounting and demounting a semiconductor device using the same, and a socket for a semiconductor device.
2. Description of the Related Art
Various tests are conducted on a semiconductor device to be mounted in an electronic apparatus or the like to eliminate any potential defect of the same at a stage prior to the mounting. A socket for a semiconductor device used in such a test is generally referred to as an IC socket. For example, as described in Japanese Patent Application Laid-open Hei 8-138812 (1996), such a socket is disposed on a printed wiring board having an input/output portion to which a predetermined test voltage is supplied and which transmits an abnormality detection signal indicating a short circuit and the like from a semiconductor device.
For example, as described in Japanese Patent Application Laid-open Hei 8-138812 (1996), a socket for a semiconductor device comprises a socket main body secured on a printed wiring board and having a housing portion for housing a contact operating member to be described later such that it can be moved relative to a pair of movable contact portions of contact terminals, a guide member having a housing portion in which a semiconductor device, e.g., a BGA type (Ball Grid Array) semiconductor device is mounted, for guiding the semiconductor device to the housing portion and positioning the semiconductor device relative to the contact terminals, a contact operating member provided in the socket main body so as to be moved reciprocally along a predetermined direction, the contact operating member for moving one of the movable contact portions of the contact terminals toward or away from the other movable contact portion, and a cover member which transmits an applied operating force to the contact operating member as a driving force through a driving mechanism of the contact operating member.
The socket main body has the housing portion therein from which a pair of movable contact portions of a plurality of contact terminals protrudes. Each of the contact terminals comprises a fixed terminal on a base end thereof which is provided on the socket main body in association with electrode portions of a semiconductor device that is mounted and a pair of movable contact portions which selectively pinch or release the electrode portions of the semiconductor device coupled to the terminal. According to a movement of the contact operating member, the pair of movable contact portions approach each other to pinch the electrode portions of the semiconductor device or move away from each other to release the electrode portions of the semiconductor device.
The contact operating member is disposed in the housing portion of the socket main body such that it can move along the moving directions of the movable contact portions of each contact terminal. For example, as described in Japanese Patent No. 3257994, there is a proposal in which the contact operating member is disposed such that it can move along a direction substantially orthogonal to the moving directions of the movable contact portions of each contact terminal.
The contact operating member has an opening therein from which the movable contact portions of each contact terminal protrude. Openings in different rows are partitioned by respective partition walls.
In the contact operating member, a movable contact pressing portion is provided at each of adjoining pairs of openings in the same row from which the movable contact portions of the contact terminal protrude, the pressing portion being formed so as to separate one of the movable contact portions from the other movable contact portion.
Further, an urging member for urging the contact operating member back to an initial position is provided between one end of the contact operating member and an inner circumferential part of the housing portion of the socket main body.
Further, the contact operating member is linked with a driving mechanism constituted by a lever and a pin as disclosed in Japanese Patent Application Laid-open Hei 8-138812 (1996) and Japanese Patent Application Laid-open Hei 9-245920 (1997). One end of the lever of the driving mechanism touches on an end of the cover member.
Thus, when the contact operating member is moved against the urging force of the urging means as the cover member is moved downward, the movable contact pressing portions are made to move such that one of the movable contact portions of each contact terminal is moved away from the other contact portion. On the contrary, the contact operating member is made to move by the urging force of the urging means and a restoring force of the one of the movable contact portions as the cover member is moved upward.
The cover member has an opening therein, the opening encircling the outer circumference the guide member. The cover member is supported on the socket main body such that it can be moved up and down relative to the socket main body.
In such a configuration, when a semiconductor device held by a hand of a transportation robot that is omitted in the illustration is mounted in the housing portion of the guide member through the opening in the cover member, the cover member is first moved down to its lowermost position by a pressing portion of the transportation robot and the semiconductor device is also moved downward.
Thus, the contact operating member is made to move against the urging force of the urging means.
Next, the semiconductor device is dropped to be placed in the housing portion of the guide member in the condition in which the movable contact pressing portions have been moved such that one of the movable contact portions of each contact terminal is moved away from the other movable contact portion and then held, and an electrode portion of the semiconductor device is thus positioned between one of the movable contact portions of each contact terminal and the other movable contact portion.
When the cover member is moved upward with each electrode of the semiconductor device disposed between the pair of movable contact portions of the respective contact terminal, the contact operating member is moved to the initial position by the urging force of the urging means and the restoring force of the one of the movable contact portions, whereby the movable contact pressing portion is moved away from the one of the movable contact portion to be put close to the other movable contact portion.
Therefore, each electrode portion of the semiconductor device is pinched by the pair of movable contact portions of the respective contact terminal, and each electrode portion of the semiconductor device is thereby electrically connected to the respective contact terminal.
In such a socket for a semiconductor device, when a semiconductor device is mounted on the guide member, the semiconductor device placed on the guide member may be jumped up if each electrode portion of the semiconductor device is pinched between the pair of movable contact portions of the respective contact terminal in an insufficient state of insertion or if the printed wiring board vibrates due to deflection of the same attributable to the operation of moving the cover member up and down.
As a measure to take in such a situation, as described in Japanese Patent No. 3257994 by way of example, it has been proposed to provide a latch mechanism having a presser member for holding the semiconductor device placed on the guide member by pressing it against each contact terminal. The presser member of the latch mechanism is configured to assume a holding position and a standby position in conjunction with the upward and downward movements of the cover member.